1. Field of the Invention
This invention relates to vacuum-type street sweepers.
2. Related Art
Vacuum sweepers, especially those used for parking lots and on roadways and sidewalks, are well known in the industry. Various types of vacuum sweepers, from commercial units to small personal units, are manufactured by a number of companies, including Elgin Sweeper Company (e.g., GeoVac), Schwarze Industries (e.g., A-series, EV-series, M-series and S-series), Python Manufacturing, Inc. (e.g., Raven 45), and Tymco Inc. (e.g., Models 210, 435, OST-4, 600, OST-6, and 600 HSP). Typically, vacuum sweepers include transition tubes, such as air flow transition tubes, air intake tubes and hopper tubes, that help facilitate moving the swept material from one or more vacuum heads into a hopper.
Conventionally, these transition tubes are typically constructed of metals, including steel, steel alloys or aluminum, and various polymers. Transition tubes are subject to a great deal of wear and tear due to the impact and abrasion that occurs as the vacuumed particles and other fluent materials move through the transition tubes from the vacuum heads into the hopper.